1. Field of the Invention
The present invention relates to a touch pad device used to guide a pointing device displayed on a display panel of an electronic apparatus and, more specifically, to a touch pad device for use with electronic devices, such as a computer system or portable computer, that is liquid resistant.
2. Background Art
To allow users to more effectively, easily and conveniently use a variety of electronic appliances, such as television sets, computers and audio systems, it is preferable that the electronic appliances have display panels that allow a user to select various functions or commands via a display panel. To properly select various functions, which can be displayed in an icon fashion on a display panel, a cursor type of icon is necessary to allow the user select individual function icons. Various devices have been developed to allow a user to control a pointing device on a display panel.
One method of controlling on screen cursors is to use a keyboard. Some techniques for constructing keyboards that can control an on screen cursor are shown, for example, in U.S. Pat. No. 4,396,830 to Isozaki entitled Waterproof Keyboard Device, U.S. Pat. No. 5,300,742 to Huang entitled Waterproof Structure for Computer Key Switch, U.S. Pat. No. 5,626,222 to Aguilera entitled Force Controllable Shielded Mechanical Switch Actuators, and U.S. Pat. No. 5,180,237 to Chen entitled Keyboard for Under Water Use.
Another method of controlling on screen cursors is by using touch control systems, similar to that detailed, for example, in U.S. Pat. No. 5,572,205 to Caldwell entitled Touch Control System. An improved method of controlling on screen cursors is the `mouse` that allows a user to more easily move a cursor on a display panel. An advanced form of a `mouse` is shown, for example, in U.S. Pat. No. 5,355,148 to Anderson entitled Fingerpoint Mouse. A more recent development in cursor control devices is the pointing stem. One type of pointing stem is shown, for example, in U.S. Pat. No. 5,508,719 to Gervais entitled Pressure-Actuated Pointing Device.
Another development that has occurred in efforts to replace the mouse is the development of a touch pad. The touch pad consists of a rectangular pad whose surface is mapped to correspond to the display panel. By touching a location on the touch pad, the computer user directs the computer to move the cursor to the corresponding location on the display panel. In addition, touch pads have been used to allow easy and reliable input into electronic appliances. Such touch pad devices have also been used with electronic appliances having liquid crystal displays or cathode ray tubes, such as the portable computer mentioned above.
The touch pads of the contemporary art do not always resist liquid well enough to prevent a user from damaging an electrical apparatus due to operating the touch pad with wet fingers or otherwise allowing liquid to come into contact with the touch pad. As such, I believe that it may be possible to improve on the contemporary art by providing a touch pad that is resistant to liquids, that prevents damage to electrical devices, that is usable with computer systems, that is economical to manufacture, that requires few manufacturing steps to produce, and that is useful with a variety of electronic devices.